Buggy code:
public class ContactManagerTester { static final int INVALID_ID = 99 ; static final int PAST_MEETING_ID = 1 ; static final int FUTURE_MEETING_ID = 2 ; ContactManager manager ; Set < Contact > allContacts ; Calendar pastDate ; Calendar futureDate ; @ Before public void setUp ( ) { } @ After public void tearDown ( ) { } @ Test ( expected = NullPointerException . class ) public void testNewContactNameException ( ) { } @ Test ( expected = NullPointerException . class ) public void testNewContactNotesException ( ) { } @ Test public void testGettingContactByNameFromEmptyList ( ) { } private boolean hasContact ( Set < Contact > set , String name ) { } @ Test public void testGettingSingleContactByName ( ) { } @ Test public void testGettingNonExistingContact ( ) { } @ Test public void testGettingEmptyNamedContact ( ) { } @ Test public void testGettingSimilarilyNamedContacts ( ) { } @ Test ( expected = IllegalArgumentException . class ) public void testGettingContactNegativeIdException ( ) { } @ Test ( expected = IllegalArgumentException . class ) public void testGettingContactNonExistingIdException ( ) { } @ Test public void testGettingContactsViaID ( ) { } @ Test ( expected = IllegalArgumentException . class ) public void testAddFutureMeetingTimeException ( ) { } @ Test ( expected = IllegalArgumentException . class ) public void testAddUnknownContactToFutureMeetingException ( ) { } @ Test public void testAddAndGetFutureMeetings ( ) { } @ Test public void testGettingNonExistingMeeting ( ) { } @ Test ( expected = IllegalArgumentException . class ) public void testAddUnknownContactToPastMeetingException ( ) { } @ Test ( expected = IllegalArgumentException . class ) public void testAddEmptyContactListToPastMeetingException ( ) { } @ Test ( expected = NullPointerException . class ) public void testNullForContactListToPastMeetingException ( ) { } @ Test ( expected = NullPointerException . class ) public void testNullForDateToPastMeetingException ( ) { } @ Test ( expected = NullPointerException . class ) public void testNullForTextToPastMeetingException ( ) { } @ Test public void testAddAndGetPastMeetings ( ) { } @ Test ( expected = IllegalArgumentException . class ) public void testGetPastMeetingException ( ) { } @ Test public void testGetNonExistentPastMeeting ( ) { } @ Test public void testGetPastMeeting ( ) { } @ Test ( expected = IllegalArgumentException . class ) public void testGetFutureMeetingException ( ) { } @ Test public void testGetNonExistentFutureMeeting ( ) { } @ Test public void testGetFutureMeeting ( ) { } @ Test public void testMeetingIds ( ) { } @ Test ( expected = IllegalArgumentException . class ) public void testGetFutureMeetingListUnknownContactException ( ) { } @ Test public void testGetEmptyFutureMeetingListWithContact ( ) { } private Contact getContact ( Set < Contact > contacts , String name ) { } @ Test public void testGetFutureMeetingListWithContact ( ) { } @ Test ( expected = IllegalArgumentException . class ) public void testGetPastMeetingListUnknownContactException ( ) { } @ Test public void testGetEmptyPastMeetingListWithContact ( ) { } @ Test public void testGetPastMeetingListWithContact ( ) { } @ Test public void testGetEmptyMeetingListWithDate ( ) { } @ Test public void testGetMeetingListWithDate ( ) { List < Meeting > future = manager . getFutureMeetingList ( futureDate ) ; assertEquals ( 1 , future . size ( ) ) ; <START_BUG> Set < Contact > one = manager . getContacts ( 0 ) ; <END_BUG> manager . addFutureMeeting ( one , futureDate ) ; future = manager . getFutureMeetingList ( futureDate ) ; assertEquals ( 2 , future . size ( ) ) ; } No newline ; at end ; of file ; }

Fix:
Set < Contact > one = manager . getContacts ( 1 ) ;